© 2004 IBM Corporation IBM ^ z/VM Module 2: Conversational Monitor System (CMS)

© 2004 IBM Corporation IBM ^ Objectives  List z/VM’s base components and describe how they work together  Describe CMS and the tasks it can accomplish  State why CMS Pipelines are an important feature of z/VM  Describe CMS Application Multitasking  Describe the XEDIT environment and its purpose

© 2004 IBM Corporation IBM ^ Objectives continued  Describe the three important application environments that CMS supports: –Callable Service Library (CSL) –OpenExtensions –Reusable Server Kernel  Show how to find and use the Help Facility  Explain Shared File System (SFS) setup and configuration  Explain how syntax diagrams are used  List and describe the most important and useful CMS commands

© 2004 IBM Corporation IBM ^ Introducing z/VM’s Base Components  Conversational Monitor System (CMS)  An end-user interface for running user programs  Control Program (CP)  A component that manages the resources of a single system to make it appear that multiple computing systems exist  REXX/VM  A programming language that allows you to write customized application programs and command procedures  Group Control System (GCS)  A virtual machine supervisor that provides multitasking services

© 2004 IBM Corporation IBM ^ Introducing z/VM’s Base Components continued  Transparent Services Access Facility (TSAF)  APPC/VM VTAM Support (AVS)  Virtual Machine Serviceability Enhancements Staged/Extended (VMSES/E)  Dump Viewing Facility

© 2004 IBM Corporation IBM ^ What is CMS?  Conversational Monitor System is an operating system environment itself  Over time CMS became a part of VM  CMS is a single user operating system, which makes it possible to:  Create and maintain files  Write and execute application programs  CMS communicates with users through the console

© 2004 IBM Corporation IBM ^ CMS Tasks With CMS, you can:  Write, test, and debug application programs for use on CMS or guest systems  Run application programs developed on CMS or guest systems  Create and edit data files  Process jobs in batch mode  Share data between CMS and guest systems  Communicate with other system users

© 2004 IBM Corporation IBM ^ Structure of CMS

© 2004 IBM Corporation IBM ^ Callable Services Library (CSL)

© 2004 IBM Corporation IBM ^ CMS Pipelines  Provide a rich and efficient set of functions that can be used to solve large problems by breaking them up into smaller programs  Smaller programs are called stages  Stages:  Read data  Filter and refine data  Combine multiple data items

© 2004 IBM Corporation IBM ^ CMS Pipelines

© 2004 IBM Corporation IBM ^ Pipeline Example pipe < profile exec | count lines | console  This command executes the number of lines contained within your PROFILE EXEC file.

© 2004 IBM Corporation IBM ^ CMS Application Multitasking  An application can be divided into multiple units of execution, called threads.  Threads have the ability to run on multiple CPUs at the same time  Multitasking facilities allow applications to harness the power of the underlying multiprocessor complex to achieve high performance.

© 2004 IBM Corporation IBM ^ OpenExtensions  OpenExtensions provides open systems support in two ways:  OpenExtensions Services  OpenExtensions Shell and Utilities  OpenExtensions Services include:  POSIX.1—System Interfaces  POSIX.1a—Extensions to POSIX.1  POSIX.1c—Threads

© 2004 IBM Corporation IBM ^ OpenExtensions – Invocation  Invocation from REXX Procedures example  OPENVM is a z/VM subcommand environment  OPENVM makes invocation of callable services look like other requests for host functions  The OPENVM language binding file defines REXX variables used by the OpenExtensions services. You include the file using the APILOAD function.

© 2004 IBM Corporation IBM ^ Reusable Server Kernel  Enables vendors and application programmers to write multithreaded server programs  The server kernel is the starting point for a server program  To construct a server program you need:  A text library of routines  A macro library of function prototypes  Constant definitions  These entities are supplied by the Reusable Server Kernel

© 2004 IBM Corporation IBM ^ Additional RSK Help Areas  Connectivity  DASD I/O  Authorization  Memory management  Runtime environment  Worker machines  Configuration and operation

© 2004 IBM Corporation IBM ^ XEDIT

© 2004 IBM Corporation IBM ^ XEDIT continued

© 2004 IBM Corporation IBM ^ XEDIT continued

© 2004 IBM Corporation IBM ^ The Batch Facility  Can take over both short and long processing jobs for you  Frees up your time to continue working at your terminal  Two examples: –Have the facility format text and send it to the printer, instead of doing it yourself –Have large jobs run throughout the night to take advantage of lower computing costs

© 2004 IBM Corporation IBM ^ How the VM Batch Facility Works  The process starts when you submit a job to the VM Batch Facility  The monitor virtual machine receives your job and holds it until it can start  A task virtual machine runs your job  The monitor machine periodically checks your job while it runs  Your commands can retrieve the status of a job, change how and when it is to run, and cancel a job  When your job is completed, the task machine logs off and is ready for another job

© 2004 IBM Corporation IBM ^ z/VM Help Facility  CMS Help Facility provide assistance for:  Tasks  Commands and options  Subcommands  REXX statements  Callable routines  Pipeline stages  Assembler language macros  Messages

© 2004 IBM Corporation IBM ^ Shared File System (SFS)  Files are stored in file pools  A user can be given an amount of file space in a pool  The files in a file space are organized in directories  A file can be placed in more than one directory

© 2004 IBM Corporation IBM ^ Shared File System (SFS) continued  Users can grant each other authorities for files or directories  Multiple users can have concurrent access to the same file or directory  Locks on files and directories ensure data integrity among multiple users  You can share files and directories with users on other systems

© 2004 IBM Corporation IBM ^ Syntax Diagrams (basics)  Read syntax diagrams from left to right and from top to bottom  This side module shows you descriptions and examples

© 2004 IBM Corporation IBM ^ CMS Commands

© 2004 IBM Corporation IBM ^ QUERY

© 2004 IBM Corporation IBM ^ QUERY – Usage Notes

© 2004 IBM Corporation IBM ^ SET

© 2004 IBM Corporation IBM ^ ACCESS

© 2004 IBM Corporation IBM ^ ACCESS

© 2004 IBM Corporation IBM ^ ACCESS – Usage Notes  Using the ACCESS command with a directory ID or a device number –With and without a file pool  Using the ACCESS command with a directory ID –Determining status by ownership  Using the ACCESS command with a virtual device number –Access can create a file directory in your virtual machine when one is not present

© 2004 IBM Corporation IBM ^ RELEASE  The RELEASE Command is used to free an accessed disk that was previously accessed with the ACCESS Command.  Example:  release 0293

© 2004 IBM Corporation IBM ^ RELEASE  If you want to release and detach the 498 disk that is accessed as your file mode b, then issue:  release 498 (det OR -- release b (det  To just release the disk currently accessed as file mode c, issue:  release c

© 2004 IBM Corporation IBM ^ FORMAT

© 2004 IBM Corporation IBM ^ FORMAT – Usage Notes  Examples of RECOMP and LABEL: –format 192 b (recomp) –format 193 c (label)  Formatting a disk requires heavy processor utilization, so can be slow and affect performance  Choose the appropriate block size to optimize: –space utilization –performance  Automatic formatting is possible on the 192 disk

© 2004 IBM Corporation IBM ^ Conclusion  CMS – Conversational Monitor System  Is a operating system that runs within z/VM  CMS tasks include writing, testing, and debugging application programs to be used by CMS or z/VM guest systems  CMS runs the full-screen editing facility called XEDIT  The CMS help facility is a CMS Command that can be accessed when help is needed by entering:  help cms

© 2004 IBM Corporation IBM ^ Glossary Conversational Monitor System (CMS)- A component of z/VM that runs in a virtual machine and provides both the interactive z/VM end-user interface and the general z/VM application programming interface. CMS runs only under the control of the z/VM Control Program (CP). CMS Pipelines- CMS job control product for z/VM that enables complex tasks to be specified and executed. CMS Pipelines has three parts – a command parser, a library of built-in programs, and a dispatcher. Callable Services Library-A package of CMS routines that can be stored as an entity and made available to a high-level language, REXX, or an assembler program.

© 2004 IBM Corporation IBM ^ Glossary File pool-A collection of minidisks managed by a file pool server. It contains user files and directories and associated control information. The files and directories for many users can be contained in a single file pool. Group Control System (GCS)- A component of z/VM, consisting of a named saved system that the user can IPL and run in a virtual machine. It provides simulated MVS services and unique supervisor services to help support a native SNA network. Initial Program Load (IPL)- The process of loading an operating system into a machine OpenExtensions Services- The VM implementation of three POSIX standards

© 2004 IBM Corporation IBM ^ Glossary OpenExtensions Shell and Utilities- provides application development tools and an interactive environment in support of the POSIX application environment. REXX/VM- (REstructed eXtended eXecutor programming language) processes English-like commands. XEDIT- A full-screen editing facility that runs under CMS.

© 2004 IBM Corporation IBM ^ References  CMS Command and Utility Reference. Manual Number: SC Third Edition (May 2002).  CMS User’s Guide. Manual Number: SC First Edition (July 2001).